JPH0694471A - Navigation system - Google Patents

Abstract

PURPOSE:To correct a self-navigation device when the self-navigation device makes an error in position measurement. CONSTITUTION:A position correction processing part 5 selectively outputs the measurement position determined by a self-navigation processing part 4 as an output present position when the flag from the self-navigation processing part 4 shows that the measurement position of the self-navigation processing part is situated on or near a road in road map information. In other cases, the distance between the measurement position determined by a radio navigation processing part 1 and the measurement position determined by the self- navigation processing part 4 is calculated, and when the distance between the two coordinates is a determined value or more, the measurement position determined by the radio navigation processing part 1 is taken as the present position, and the traveling start coordinate managed by the self-navigation processing part 4 is corrected to the determined present position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for position measurement in a navigation system for a mobile body such as an automobile.

[0002]

2. Description of the Related Art As a conventional technique for position measurement in a navigation system for a vehicle, a navigation system disclosed in Japanese Patent Laid-Open No. 1-316607 is known.

This navigation device includes a radio navigation device that measures its own position by using radio waves from artificial satellites, and a self-contained navigation device that measures its own position by using various sensors and road map information. If the difference between the measurement position obtained by the radio navigation device and the measurement position obtained by the self-contained navigation device exceeds a predetermined value, the measurement result by the self-contained navigation device or the measurement result by the self-contained navigation device is Correct the offset of the measurement value by the radio navigation device using the result of processing with a predetermined filter as the estimated value of the position, and conversely, if the difference does not exceed the predetermined value, the measurement result by the radio navigation device or The drift of the measurement value by the self-contained navigation device is corrected by using the result obtained by processing the measurement result by the radio navigation device by a predetermined filter as an estimated value of the position.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
According to the navigation device described in Japanese Patent Publication No. 7, when the difference between the measurement position obtained by the radio navigation device and the measurement position obtained by the self-contained navigation device exceeds a predetermined value, the measurement result by the self-contained navigation device is displayed. If the difference does not exceed a predetermined value, the measurement result by the radio navigation device is emphasized.

For this reason, for example, the position measurement by the radio navigation device cannot be used due to geographical factors, etc., and the position measured by the self-contained navigation device is erroneous during the period of traveling only by the self-contained navigation device. If it happens, the following problems will occur.

That is, in this case, when the position measurement by the radio navigation device is resumed thereafter, the difference between the measurement position by the radio navigation device and the measurement position by the self-contained navigation device is
Although it exceeds a predetermined value, at this time, since the device attaches importance to the measurement result by the self-contained navigation device and erroneously corrects the offset of the measurement value by the radio navigation device, accurate position measurement is performed. There was a problem that it could not return to operation.

Therefore, it is an object of the present invention to provide a navigation device capable of more accurately measuring a position even under various circumstances.

[0008]

[Means for Solving the Problems] To achieve the above object,
The present invention is a navigation device that is mounted on a moving body and outputs the current position of the moving body, and a radio navigation means that measures the current position of the moving body based on radio waves from an artificial satellite, and an angular velocity or a geomagnetic angle. Direction measuring means for measuring the traveling direction of the moving body based on at least one of the following, distance measuring means for measuring the traveling distance of the moving body, storage means for storing road map information, and given traveling start point position From the present to the present, using the traveling azimuth measured by the azimuth measuring means and the traveling distance measured by the distance measuring means, the provisional present position or traveling history of the moving body is obtained, and the obtained provisional present position or Self-contained navigation means for determining the current position of the moving body by collating the travel history with the road map information read out from the storage means, and the current position and the radio navigation operator determined by the self-contained navigation means. When the current position determined by is not separated by a predetermined distance or more, the current position determined by the self-contained navigation means is output as the final current position, and when it is separated by a predetermined distance or more, the radio navigation means is determined. In addition to outputting the final current position, the navigation device is provided with position correction means for providing the self-contained navigation means with the current position determined by the radio navigation means as a new traveling start point.

Desirably, the vehicle is equipped with traveling speed measuring means for measuring the traveling speed of the moving body, and the radio navigation means also measures the moving direction of the moving body on the basis of radio waves from an artificial satellite. When the position correction means outputs the final current position determined by the radio navigation means and gives the self-contained navigation means the current position determined by the radio navigation means as a new traveling start point, the traveling speed The traveling speed measured by the measuring means determines whether or not a predetermined value or more,
When the value is equal to or more than a predetermined value, it is preferable to include an azimuth correcting unit that corrects the azimuth measuring unit with the moving direction of the moving body measured by the radio navigation unit as the current traveling azimuth.

[0010]

The position correcting means according to the present invention corrects the position of the self-contained navigation by judging the deviation between the position of the radio navigation and the position of the self-contained navigation so that the position error of the navigation device becomes less than the predetermined distance. In addition, it is desirable to determine the accuracy of the self-contained navigation determined from the deviation between the position by radio navigation and the position by self-contained navigation, the relationship between self-contained navigation and road map information, and the history of the position by self-contained navigation. By correcting the position of, the position error of the navigation device is within the position error with respect to the travel distance when traveling on the road indicated in the road map information, and less than the predetermined distance when traveling on other roads. Try to be. Also, preferably,
Correct the position of self-contained navigation by judging the deviation between the position by radio navigation and the position by self-contained navigation, the relationship between self-contained navigation and road map information, and the accuracy of self-contained navigation judged from the history of position by self-contained navigation. The position error of the navigation device is set to be less than the predetermined distance when there is a high possibility that the wrong position is indicated even when traveling on the road indicated by the road map information. Also, it is desirable to correct the position of self-contained navigation by judging the accuracy of the radio navigation from the position history of the radio navigation and correct the position of the self-contained navigation so that it will not be corrected to the wrong position. Can be

On the other hand, the azimuth correcting means corrects the traveling azimuth of the moving body in time when the position of the self-contained navigation is corrected, and improves the accuracy of the self-contained navigation after correcting the traveling start point of the self-contained navigation.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the navigation device according to the present invention will be described below by taking it as an example when it is mounted on an automobile.

First, a first embodiment of the navigation system according to the present invention will be described.

FIG. 1 shows the configuration of the navigation system according to the first embodiment.

In the figure, reference numeral 1 is a radio-navigation processing unit, which determines a current position (Gx, Gy) by using a triangulation technique based on a signal from an artificial satellite (not shown). Reference numeral 2 denotes an azimuth measurement processing unit, which uses angular velocity data from an angular velocity sensor (not shown), geomagnetic data from a geomagnetic sensor (not shown), or data from both sensors to detect the traveling direction of the vehicle. Is calculated and output. A distance measurement processing unit 3 measures and outputs the traveling distance of the vehicle based on a pulse input from a distance sensor (not shown).

Reference numeral 4 denotes a self-contained navigation processing unit, which manages a certain traveling start point set manually or automatically, and the distance data of the distance measurement processing unit 2 and the azimuth of the azimuth measurement processing unit 3 from this traveling start point. The data is integrated to calculate the current estimated position, and the estimated position or the driving history up to the present with the estimated position as the end point is compared with the road map information read from the storage device (not shown) to measure the position ( Mx,
My) is determined.

Reference numeral 5 denotes a position correction processing unit which inputs the position (Gx, Gy) by the radio navigation processing unit 1 and the position (Mx, My) by the self-contained navigation processing unit 4 and inputs the position based on a predetermined determination method. (Gx, Gy) or position (Mx, My) is selectively output as the output current position (X, Y). Further, when the position (Gx, Gy) by the radio navigation processing unit 1 is selected as the output current position (X, Y), the traveling start point managed by the self-contained navigation processing unit 4 is updated by the output current position (X, Y). .

Next, the operation of the navigation system according to the first embodiment will be described.

First, FIG. 2 shows a processing procedure performed by the position correction processing section 5 of the navigation device according to the first embodiment.

As shown in the figure, the position correction processing unit 5 performs the process S1 in the radio navigation processing unit 1 at the current position (Gx,
Gy) is determined, and the current position (Gx,
If Gy) is obtained, the process proceeds to step S2, and if the current position (Gx, Gy) is not obtained, the process proceeds to step S3.

Then, in step S2, the radio navigation processing section 1
The position (Gx, Gy) by the self-contained navigation processing unit 4 and the position (Mx, My) by the self-contained navigation processing unit 4 are calculated. If it is determined that the value is less than the predetermined value α, the process proceeds to step S3.

On the other hand, in the process S3, the position (Mx, My) by the self-contained navigation processing unit 4 is selectively output as the output current position (X, Y), and the series of processes is ended.

In step S4, (Gx, Gy) obtained by the radio navigation processing section 1 is selected and output as the output current position (X, Y), and the procedure proceeds to step S5, in which the self-contained navigation controlled by the self-contained navigation processing section 4 is executed. The position (X,
The correction is made in Y) and a new traveling start point is set, and a series of processing is ended.

By the above processing procedure, the position measuring operation of the navigation system according to the first embodiment is as follows.

FIG. 3 shows an operation example of the navigation device according to the first embodiment.

In FIG. 3, Gi represents (Gx, Gy) obtained by the radio navigation processing unit 1, and Mi represents the self-contained navigation processing unit 4.
Represents (Mx, My). Also, i (i = 1,
2, ..., N) represent the position corresponding to the time. The solid line represents the actual travel path, and the dotted line represents the travel path by the navigation device.

Firstly, i = G ₁ is 1 point, the distance d ₁ between M ₁ is outputted current position the position obtained by autonomous navigation processing unit 4 for less than the predetermined value _{α (Mx 1, My 1)} ( X ₁ ,
Output as Y ₁ ).

Next, at the point of i = 2, since the (Gx, Gy) obtained by the radio navigation processing unit 1 is not obtained, the position (Mx ₂ , My ₂ ) obtained by the self-contained navigation processing unit 2 is output. Output as the current position (X ₂ , Y ₂ ).

Further, since the point i = 3 is a distance d ₃ between the G _3, M ₃ is equal to or higher than the predetermined value alpha, the input position determined by radio navigation unit 1 (Gx _3, Gy ₃₎ an output current The position (X ₃ , Y ₃ ) is output, and at the same time, the traveling start point position (Mx ₃ , My ₃ ) managed by the self-contained navigation processing unit 2 is calculated as the position (X ₃ ,
Correct with Y ₃ ) and make a new starting point. That is, the self-contained navigation will restart from the position of the position M ₃ a.

As a result, the component of the measurement error up to the present in the self-contained navigation processing unit 4 has been eliminated, and G ₄ and M ₄ at the point of i = _4.
The distance d ₄ between them becomes less than the predetermined value α, and the self-contained navigation processing unit 4 obtains the output current position (X ₄ , Y ₄ ) (Mx
₄ , My ₄ ) is output.

As described above, even if the actual traveling locus and the traveling locus by the self-contained navigation are deviated (even if the traveling azimuth of the vehicle is deviated by the azimuth measurement processing unit), the position error of the navigation device is converged to less than the predetermined distance. be able to.

The predetermined value α may be a fixed value or a variable value that changes according to some parameter.

A second embodiment of the navigation system according to the present invention will be described below.

Next, a second embodiment will be described with reference to FIGS.

FIG. 4 shows the structure of the navigation system according to the second embodiment. As shown in the figure, in the configuration of the navigation device according to the second embodiment, in the configuration of the navigation device according to the first embodiment (see FIG. 1), the self-contained navigation processing unit 2 outputs a flag. It is a thing. This flag has a value of 1 when the position (Mx, My) measured by the self-contained navigation processing unit 4 is on or near the road in the road map information,
When there is no flag, the flag indicates 0, and the self-contained navigation processing unit 4
Is generated by comparing the measured position (Mx, My) with the road map information.

Next, the operation of the navigation system according to the second embodiment will be described.

FIG. 5 shows a processing procedure of processing performed by the position correction processing unit 5 according to the second embodiment.

As shown in the figure, the position correction processing unit 5 determines whether or not the current position (Gx, Gy) has been obtained by the radio navigation processing unit 1, and if the current position (Gx, Gy) has been obtained, the processing is performed. Proceed to S6, current position (Gx, Gy)
If is not required, the process proceeds to step S3.

In process S6, the flag from the self-contained navigation processing unit 4 is determined, and when the flag is 1 (when the measurement position of the self-contained navigation processing unit is on or near the road in the road map information), the self-contained navigation process is performed. Measurement position (Mx, M
y) is highly reliable, the process proceeds to step S3, and (Mx, My) obtained by the self-contained navigation processor 4 is output. Current position (X, Y)
Is selected and output, and a series of processing is ended. On the other hand, when the flag is 0, the process proceeds to step S2.

In step S2, the radio navigation processing unit 1 obtains (Gx, Gy) and the self-contained navigation processing unit 4 obtains (Mx, M).
y) is calculated, and if the distance between the two coordinates is determined to be equal to or greater than the predetermined value α, the process proceeds to step S4, and if it is determined to be less than the predetermined value α, the process proceeds to step S3.

In step S4, (Gx, Gy) determined by the radio navigation processing section 1 is selected and output as the output current position (X, Y), and the flow advances to step S5.

In step S5, the coordinates of the starting point of the self-contained navigation are corrected at the position (X, Y) selected in step S4 to make a new starting point of the running, and the series of processes is completed.

As described above, according to the second embodiment, when the measurement position of the self-contained navigation processing unit is on or near the road in the road map information, the measurement position (Mx, My) of the self-contained navigation processing unit 4 is obtained. By trusting), even if the radio navigation processing unit 3 measures an erroneous position, the accurate position can be determined.

Next, a third embodiment of the navigation system according to the present invention will be described.

FIG. 6 shows the configuration of the navigation system according to the third embodiment. As shown in the figure, the configuration of the navigation device according to the second embodiment is the same as the configuration of the navigation device according to the second embodiment described above (see FIG. 4). (Mx, My) obtained by the self-contained navigation is output as a numerical value of the probability of being on or near the road in the road map information. This accuracy is obtained by calculating the ratio of the distance that the measurement position was on or near the road during the predetermined travel distance to the predetermined travel distance in the past, and when the current measurement position is not on or near the road. Is calculated by subtracting a value corresponding to the travel distance or the travel time from the last point on or near the road from the above ratio. Or
The ratio is simply taken as the accuracy.

FIG. 7 shows a processing procedure performed by the position correction processing section 5.

As shown in the figure, in the third embodiment, first, in step S1, it is determined whether or not the current position (Gx, Gy) has been obtained by the radio navigation processing unit 1, and the current position (Gx, Gy) is determined. If the current position (Gx, Gy) has not been calculated, the process proceeds to step S6.

In step S6, the flag from the self-contained navigation processing unit 4 is judged, and when the flag is 1, the self-contained navigation is calculated (M
(x, My) is on or near the road in the road map information), the process S7, and when the flag is 0, the process S7.
Go to 2.

In step S7, the accuracy from the self-contained navigation processing unit 4 is determined, and if the accuracy is equal to or higher than a predetermined value β (when (Mx, My) obtained by self-contained navigation is calculated with the accuracy equal to or higher than β), the processing is executed. If the accuracy is less than β in S3, the determination that the vehicle is on or near the road is not trusted, and the process proceeds to S2.

In step S2, the radio navigation processing section 1 obtains (Gx, Gy) and the self-contained navigation processing section 4 obtains (Mx, M).
y), the process proceeds to step S4 when the distance between the two coordinates is determined to be greater than or equal to the predetermined value α, and proceeds to process S3 when determined to be less than the predetermined value α.

In step S3, (Mx, My) obtained by the self-contained navigation processing section 4 is selected and output as the output current position (X, Y), and a series of processing ends.

In step S4, (Gx, Gy) obtained by the radio navigation processing section 1 is selected and output as the output current position (X, Y), and the flow advances to step S5.

In process S5, the coordinates of the traveling start point in self-contained navigation are set at the position (X, Y) selected in process S4 to set a new traveling start point, and the series of processes is terminated.

As described above, according to the third embodiment, in addition to the navigation device according to the second embodiment, the output current position is considered in consideration of the certainty of the measurement position of the self-contained navigation processing unit 4. Can be determined, and the position can be determined more accurately.

The fourth embodiment of the navigation system according to the present invention will be described below.

FIG. 8 shows the configuration of the navigation system according to the fourth embodiment.
Shown in.

As shown in the figure, the configuration of the navigation device according to the second embodiment is the same as the configuration of the navigation device according to the first embodiment (see FIG. 1), in which a discrete frequency is output from the radio navigation processing unit 1. It is something that is done. The discrete frequency is generated by judging whether the measurement position (Gx, Gy) by the radio navigation is the history obtained by the past radio navigation and whether it is discrete or continuous. The discrete frequency is output as a larger numerical value as it is more discrete.

FIG. 9 shows a processing procedure performed by the position correction processing section 5.

As shown in the figure, the position correction processing unit 5 is the current position (Gx,
Gy) is determined, and the current position (Gx,
If Gy) is obtained, the process proceeds to step S8, and if the current position (Gx, Gy) is not obtained, the process proceeds to step S3.

In step S8, the discrete frequency is judged, and if it is larger than the predetermined value γ, the position (Gx, Gy) is not adopted as the output current position because the reliability of the current position (Gx, Gy) is low. The process proceeds to step S3. When it is smaller than the predetermined value γ, the process proceeds to S2.

In step S2, the radio navigation processing section 1 obtains (Gx, Gy) and the self-contained navigation processing section 4 obtains (Mx, My).
y) is calculated, and if the distance between the two coordinates is determined to be equal to or greater than the predetermined value α, the process proceeds to step S4, and if it is determined to be less than the predetermined value α, the process proceeds to step S3.

On the other hand, in procedure S3, (Mx, My) obtained by the self-contained navigation processing unit 4 is selectively output as the output current position (X, Y), and a series of processing is ended.

In step S4, (Gx, Gy) obtained by the radio navigation processing section 1 is selected and output as the output current position (X, Y), and the flow advances to step S5.

In process S5, the coordinates of the starting point of the self-contained navigation are reset at the position (X, Y) selected in step S4 to make a new starting point of the running, and the series of processes is completed.

As described above, according to the fourth embodiment, the output current position can be determined in consideration of the reliability of the measurement position of the radio navigation processing unit 1, and the position can be determined more accurately. You can

Note that the radio navigation processing section 1 used in this embodiment is
The determination process (process S8) based on the discrete frequency obtained from
It can also be used in each of the above embodiments.

The fifth embodiment of the navigation system according to the present invention will be described below.

FIG. 10 shows the structure of a navigation system according to the fifth embodiment.

In the figure, reference numeral 1 denotes a radio-navigation processing unit, which obtains a current position (Gx, Gy) and a moving direction θG by using a triangulation technique using a signal from an artificial satellite (not shown).

Reference numeral 2 denotes an azimuth measurement processing unit, which advances the vehicle based on angular velocity data from an angular velocity sensor (not shown), geomagnetic data from a geomagnetic sensor (not shown), or data from both sensors. Compute and output the azimuth.

Reference numeral 3 denotes a distance measurement processing unit, which measures and outputs the traveling distance of the vehicle based on a pulse input from a distance sensor (not shown).

Reference numeral 4 denotes a self-contained navigation processing unit, which integrates the distance data of the distance measurement processing unit 2 and the azimuth measurement data of the azimuth measurement processing unit 3 from a certain traveling start point set manually or automatically to calculate an estimated position. At the same time, the estimated position or the travel history based on the estimated position is compared with the road map information read from the storage device (not shown) to measure the position (Mx, M).
y) is determined.

Reference numeral 5 denotes a position correction processing unit which inputs (Gx, Gy) obtained by the radio navigation processing unit 1 and (Mx, My) obtained by the self-contained navigation processing unit 4 to enter a predetermined determination method. Based on this, the position (Gx, Gy) or the position (Mx, My) is selectively output as the output current position (X, Y). When (Gx, Gy) obtained by the radio navigation processing unit 1 is selected as the output current position coordinates (X, Y), the traveling start point of the self-contained navigation processing unit 4 is corrected by the output current position (X, Y). At the same time, an azimuth correction request is output to the azimuth correction processing unit 6.

The azimuth correction processing unit 6 is provided when the azimuth correction processing unit 4 issues a azimuth correction processing request.
The traveling azimuth θ is corrected by the moving azimuth θG obtained by the radio navigation processing unit 1.

Next, FIG. 11 shows a processing procedure performed by the position correction processing section 5 of the navigation device in the fifth embodiment.

As shown in the figure, first, in step S1, it is determined whether or not the current position (Gx, Gy) has been obtained by the radio navigation processing section 1, and if the current position (Gx, Gy) has been obtained, step S3. If the current position (Gx, Gy) has not been obtained, the process proceeds to step S2.

In step S2, the radio navigation processing section 1 obtains (Gx, Gy) and the self-contained navigation processing section 4 obtains (Mx, M).
y) is calculated, and if the distance between the two coordinates is determined to be equal to or greater than the predetermined value α, the process proceeds to step S4, and if it is determined to be less than the predetermined value α, the process proceeds to step S3.

In step S3, (Mx, My) obtained by the self-contained navigation processing section 4 is selected and output as the output current position (X, Y), and a series of processing ends.

In step S4, (Gx, Gy) obtained by the radio navigation processing section 1 is selected and output as the output current position (X, Y), and the flow advances to step S5.

In the process S5, the coordinates of the starting point of the traveling in the self-contained navigation processing unit 4 are set as the new starting point of the vehicle corrected at the position (X, Y) selected in the step S4, and the process proceeds to the step S9.

In processing S9, the vehicle speed obtained from the self-contained navigation processing unit 4 is determined. If the speed V is equal to or higher than the predetermined value δ, the influence of the deviation of the traveling direction is large. If the speed V is less than the predetermined value δ, the series of processing is terminated.

In process S10, the traveling azimuth θ in the azimuth measurement processing unit 2 is corrected by the moving azimuth θG in the radio navigation processing unit 1, and the series of processes is ended.

The traveling azimuth θ in the azimuth measurement processing unit 2 when the vehicle speed V used in the fifth embodiment is not less than the predetermined value δ.
The processing for correcting the traveling direction θG obtained by the radio navigation processing unit 1 and setting the traveling direction thereafter as θ = θG (processing S9 and processing S10) can also be used in each of the above-described embodiments.

By the processing of FIG. 11 as described above,
The operation of this navigation system is as follows.

FIG. 12 shows the operation system of the navigation system according to the fifth embodiment.

In FIG. 12, Gi is the radio navigation processing section 1
Represents the (Gx, Gy), and Mi represents the (Mx, My) calculated by the self-contained navigation processing unit 4. Also, i (i = 1,
2, ..., N) represent the position corresponding to the time. The solid line represents the actual travel path, and the dotted line represents the travel path by the navigation device. It should be noted that, for simplicity of explanation, it is assumed that the vehicles are traveling straight in the same direction.

[0087] i = the distance d ₁ between G _1, M ₁ is 1 point output current position for less than a predetermined value α (X _2, Y ₂₎ is autonomous navigation processing unit 4 is determined (Mx _1, My ₁ ) is output.

[0088] i = 2 points is a distance d ₂ between G _2, M ₂ in the same manner as the processing at the point of i = 1 is output a current position for less than a predetermined value α (X _2, Y ₂₎ is self-supporting It outputs (Mx ₂ , My ₂ ) obtained by the navigation processing unit 2.

[0089] i = G ₃ is 3 points, M distance d ₃ between the ₃ outputs the current position for a predetermined value or more α (X _3, Y ₃₎ is input position by radio navigation unit 1 (Gx _3, Gy ₃ ) is output, and at the same time, the start position of the self-contained navigation (Mx ₃ , My ₃ )
Is corrected at the position (X ₃ , Y ₃ ) to make a new running start point. Therefore, the self-contained navigation will restart from the position of M3a. Further, the traveling azimuth θ in the azimuth measurement processing unit 2 is corrected by the moving azimuth θG obtained in the radio navigation processing unit 1, and the subsequent traveling azimuth is set to θ = θG.

[0090] i = the 4 point G _4, the distance d ₄ between M ₄ is output a current position for less than a predetermined value α (X _4, Y ₄₎ has autonomous navigation processing unit 4 was determined (Mx _4, My ₄ ) is output.

As described above, according to the fifth embodiment, even if the actual traveling locus is deviated from the traveling locus by the self-contained navigation (even if the traveling azimuth of the vehicle is deviated by the azimuth measurement processing unit), the navigation device The position error is less than the predetermined distance. Also,
If the speed of the vehicle is greater than or equal to a predetermined value δ, the traveling direction θ is also corrected, so that the accuracy of subsequent self-contained navigation can be improved.

As described above, according to the embodiments of the present invention,
By looking at the difference between the positions of the radio navigation and the self-contained navigation, and when the deviation becomes large, the position error of the navigation device is always kept below the predetermined distance by correcting the position of the self-contained navigation at the current position obtained by the radio navigation. Can provide a precise position. Further, it is possible to provide a more accurate position by carefully checking the accuracy of the self-contained navigation and the accuracy of the radio navigation and not using the radio navigation more than necessary. Further, when the position of the self-contained navigation is corrected by the radio navigation, the position of the vehicle can be corrected more accurately by correcting the direction of the vehicle.

[0093]

As described above, according to the present invention, it is possible to provide a navigation device capable of more accurately measuring a position even under various circumstances.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a navigation device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing a processing procedure of the navigation device according to the first embodiment.

FIG. 3 is an explanatory diagram showing an operation example of the navigation device according to the first embodiment.

FIG. 4 is a block diagram showing a configuration of a navigation device according to a second embodiment.

FIG. 5 is a flowchart showing a processing procedure of the navigation device according to the second embodiment.

FIG. 6 is a block diagram showing a configuration of a navigation device according to a third embodiment.

FIG. 7 is a flowchart showing a processing procedure of a navigation device according to a third embodiment.

FIG. 8 is a block diagram showing a configuration of a navigation device according to a fourth embodiment.

FIG. 9 is a flowchart showing a processing procedure of the navigation device according to the fourth embodiment.

FIG. 10 is a block diagram showing a configuration of a navigation device according to a fifth embodiment.

FIG. 11 is a flowchart showing a processing procedure of the navigation device according to the fifth embodiment.

FIG. 12 is an explanatory diagram showing an operation example of the navigation device according to the fifth embodiment.

[Explanation of symbols]

 1 Radio-navigation processing unit 2 Direction measurement processing unit 3 Distance measurement processing unit 4 Autonomous navigation processing unit 5 Position correction processing unit 6 Direction correction processing unit

Claims (7)

[Claims] 1. A navigation device mounted on a mobile body for outputting the current position of the mobile body, the radio navigation means for measuring the current position of the mobile body based on radio waves from an artificial satellite, and an angular velocity or geomagnetism. A direction measuring means for measuring the traveling direction of the moving body based on at least one of the angles, a distance measuring means for measuring the traveling distance of the moving body, a storing means for storing road map information, and a given traveling start point. From the position to the present, using the traveling azimuth measured by the azimuth measuring means and the traveling distance measured by the distance measuring means, the provisional present position or traveling history of the moving body is obtained, and the obtained provisional present position Alternatively, the self-sustained navigation means for determining the current position of the moving body by collating the travel history with the road map information read from the storage means, and the current position and the radio wave determined by the self-sustained navigation means If the current position determined by the navigation means is not more than a predetermined distance away, the current position determined by the self-contained navigation means is output as the final current position, and if the distance is more than the predetermined distance, the radio navigation means is provided. And a position correcting means for outputting to the self-contained navigation means the current position determined by the radio navigation means as a new traveling start point, as well as outputting the final current position determined by. 2. The navigation device according to claim 1, wherein the position correcting means separates the current position determined by the self-contained navigation means from the current position determined by the radio navigation means by a predetermined distance or more. Even if the current position determined by the self-contained navigation means is on or near the road on the road map information, the current position determined by the self-contained navigation means is output as the final current position. The navigation device, wherein the self-contained navigation means is not given the current position determined by the radio navigation means as a new traveling start point. 3. The navigation device according to claim 1, wherein in the position correcting means, the current position determined by the self-contained navigation means and the current position determined by the radio navigation means are separated by a predetermined distance or more. Even in this case, the current position determined by the self-contained navigation means is on the road map information, on the road or in the vicinity thereof, and when the accuracy of being on the road or in the vicinity thereof is a predetermined value or more, A navigation device, wherein the current position determined by the self-contained navigation means is output as a final current position, and the current position determined by the radio navigation means is not given to the self-contained navigation means as a new traveling start point. 4. The navigation device according to claim 3, wherein the accuracy is such that the current position determined by the self-contained navigation means during the predetermined traveling distance with respect to the past traveling distance is on or near the road. Navigation device characterized by a ratio of different distances. 5. The navigation device according to claim 3, wherein the certainty is the past current position determined by the self-contained navigation means during the predetermined travel distance on the road or near the road. If the current position determined by the self-contained navigation means is not on or near the road, the distance or travel time from the last point on or near the road is calculated. A navigation device characterized by being a value obtained by subtracting a corresponding value from the ratio. 6. The navigation device according to claim 1, 2, 3, 4, or 6, wherein the position correction means obtains a history of the current position determined by the radio navigation means, and the obtained history is discrete. When the current position determined by the self-contained navigation means and the current position determined by the radio navigation means are separated by a predetermined distance or more, the current position determined by the self-contained navigation means is final. Navigation device, wherein the current position determined by the radio navigation means is not provided as a new traveling start point to the self-contained navigation means. 7. A navigation device according to claim 1, 2, 3, 4, 5 or 6, further comprising a traveling speed measuring means for measuring a traveling speed of the moving body,
And, the radio navigation means also measures the moving direction of the moving body based on the radio waves from the artificial satellite, the position correction means, while outputting the final current position determined by the radio navigation means, For autonomous navigation means,
When the current position determined by the radio navigation means is given as a new traveling start point, the traveling speed measured by the traveling speed measuring means determines whether or not a predetermined value or more, and if the predetermined value or more, A navigation device comprising an azimuth correcting means for correcting the azimuth measuring means, with the moving direction of the moving body measured by the radio navigation means as the current traveling azimuth.